Time to glaucoma progression detection by optical coherence tomography and visual field in glaucoma individuals of African descent.

ABSTRACT

PURPOSE: To examine the time to glaucoma progression detection by retinal nerve fiber layer thickness (RNFLT) and visual field (VF) among African descent (AD) individuals. DESIGN: Retrospective cohort study. METHODS: Setting: Multi-center. STUDY POPULATION We included AD glaucoma eyes from DIGS/ADAGES with ≥2-year/5-visits of optic nerve head RNFLT and 24-2 VF examinations. Intervention or Observation Procedure Rates of VF mean deviation (MD) and RNFLT worsening were analyzed using linear mixed-effects models, and longitudinal data was simulated using the variability estimates. MAIN OUTCOME MEASURE: The simulated time to detect trend-based glaucoma progression was assessed with assumed rates of VF MD and RNFLT change derived from the cohort (25th, 50th, 75th percentile [p25, median, p75] slopes and mean slopes). Severity-stratified analyses were also performed. RESULTS: We included 184 eyes from 128 AD subjects (mean baseline age 63.4 years; VF MD -4.2 dB, RNFLT 80.2 µm). The p25, median, mean and p75 rates of change were -0.43, -1.01, -1.15 and -1.64 µm/year for RNFLT, and 0.00, -0.21, -0.30 and -0.51 dB/year for VF MD, respectively. Compared to VF MD, RNFLT showed an overall shorter mean time to progression detection (time difference 0.4-1.7 years), with the mean rates showing the largest difference (RNFLT 5.2 years vs. VF MD 6.9 years). Similarly, we found an overall shorter time to detect RNFLT progression, compared to that of VF MD progression, in mild glaucoma eyes (≥1 year earlier) and in moderate-advanced glaucoma eyes (∼0.5 year earlier). CONCLUSIONS: Computer simulation showed potentially shorter time to detect RNFLT progression than VF MD progression in AD eyes. Our findings support the importance of using RNFLT to detect progressive glaucoma in AD individuals.